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Help With Circuits Regarding Ohms

  1. Jun 28, 2011 #1
    Hello, I feel like an idiot because I can't answer this myself (I forgot my high school physics).

    I have a stereo amp head that has two speaker outputs at 75w each. Each of these outputs has a resistance of 8 ohms each. My cab, however, is mono, and only has 1 speaker input. The cab I own is an 8 ohm cabinet, but it is mono, and only has 1 speaker input. Would it be safe to use a y-connector to make the stereo outputs mono? I'm not sure of what the final ohms would be.

    I drew a crude circuit diagram for you all to visualize.

    http://img163.imageshack.us/img163/6374/dfgjg.jpg [Broken]

    I appreciate all the help. Thank you!

    *This is NOT a homework question. This is a question with a physics problem I encountered in REAL LIFE*
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Jun 28, 2011 #2


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    Most info I have seen wants just the left input when going to mono.
  4. Jun 28, 2011 #3
    Do NOT do this.

    You will simply damage the output sections of one or both amplifiers at best and achieve a loud bang at worst.

    You should never common the outputs of amplifiers, especially not 75 watt ones.

    It may be possible to configure the outputs to achieve what is known as a bridge configuration, but you will then require a special drives to drive the amps in antiphase. This configuration also connects speaker differentsly as well.

    Hope I am not too late.
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